Following our previous post outlining the PRCF Sumatra’s Lobugala-Negara camera trapping Project (which you can read here), Dr. Greg McCann has shared some of his notes while in the field.
EXPEDITION Study Area 1: Desa Perba Tua
While the weather was suboptimal for an expedition, with muddy and wet conditions due to intermittent heavy rain showers typical for January, the local team assembled by the village headman at Desa Perbu Tua lifted our spirits. Three experienced backwoodsmen were ready to take us up the mountain to a shelter that they had constructed—it was a relief to know that we would not necessarily have to pitch tents on a soggy jungle hillside amidst a downpour. And so off we went, into the unknown.
The health of the forest left a deep impression on us. While the plains are mostly cultivated for rice, coffee, and other agricultural products surrounding the villages in this landscape, thick hill forest generally comes right down to the edge of the paddies, with calls of Siamang Gibbons and Rhinoceros Hornbills serenading those tilling the fields every day.
While trekking up the steep terrain, we noticed abundant tracks of barking deer and wild pig—prey base for carnivores— and despite Indonesia’s regrettable caged bird trade, abundant birdsong. Not long after the sun broke through the clouds, Siamangs began calling, and the hoot of a Rhinoceros Hornbill came ever closer until we were finally able to catch a glimpse of it flying overhead. Gibbons and hornbills are two key indicator species of a healthy forest, so these were encouraging signs. I took mental note of a large fallen tree that I felt would be ideal for a camera trap placement (near which we installed one on our way out), as all manner of wildlife utilize knocked-over trees as safe, smooth, and easy walking routes.
In some areas on the lower elevations of the slopes near Perba Tua village, benzoin trees (Styrax benzoin) also known as frankincense tree or pohon kemenyan in Bahasa Indonesian, planted generations ago, are still harvested for their resin, which is exported internationally. These trees, now surrounded by healthy secondary forest, are an important source of income for local villagers and most of the work is done by women and is viewed as a source of pride for the work and revenue that they provide. Significantly, globally important wildlife such as the Siamang Gibbon and Rhinoceros Hornbill—two key indicator species of a healthy ecosystem which we heard and observed there—appear to have accepted the frankincense tree as part of its natural habitat, so this tree species is not an obstacle, as oil palm is. The tracks of deer and wild pig were also observed in this multi-use zone of the benzoin trees, and numerous species of birds were also seen and heard.
Moving farther up the mountains, the benzoin trees disappear and one enters the unique high-altitude moss forest or hutan lumut in Indonesian. In HHDSL, this was the home of Sumatran Tiger, Sunda Clouded Leopard, Asiatic Golden Cat Marbled Cat, Sumatran Serow, Sun Bear, and much more. Our camera traps will prove the veracity of the anecdotal reports we heard of the said species’ presence in LNL. Interestingly, we were also told that Dhole and Sumatran Striped Rabbit are also present; both would be exciting discoveries; both would be first records for PRCF in Sumatra, and it would be the first record of Sumatran Striped Rabbit outside of its known range in Jambi province.
After around four hours of slippery trekking up the mountain trail that is used by villagers to collect NTFPs—such as benzoin resin, wild fruits, sugar palm, and areca nuts, we arrived at a wooden shelter in the midst of misty and lush forest just as the rains resumed. We were able to get a fire started inside the shelter, find some warmth and a dry patch of floor for ourselves, and after a dinner of rice and vegetables, enjoyed a well-earned sleep.
A quick breakfast and then off to deploy more cameras, finding three optimal locations on tree-bridges and game trails, with our highest camera deployed at 1,425m asl. Best of all, our guides surprised us by bringing us to a grasslands that we had not even been able to initially find using Google Earth maps—pispis ria (in the Batak language, which translates to “grass field”). We were tempted to deploy a camera to this promising location, which rises up to the edge of the highest peak in the landscape where it meets evergreen forest. However, it was already 15:30, and we did not want to trek back down the mountain in both the dark and the rain as clouds were closing in; this extensive grassland area deserved extensive exploration, not a hasty reconnaissance, so we decided that on our return trip we would move some of the cameras that we had deployed in this study area to pispis ria. Our guides informed us that the grasslands was frequented by Sun Bears and many other species. We eagerly await exploration of pispis ria!
Upon return to Desa Perba Tua we met a hunter who spoke surprisingly good English. He told us that Sumatran Tigers were still found in the mountains, as well as Sunda Clouded Leopards, Dholes (to the best of my knowledge, Dholes have never been camera-trapped in Tapanuli district) and Malayan Tapirs.
One of our guides told us that Sunda Clouded Leopards often raided his—and other villagers’—chicken coups and said he knew the direction from which they descended from the mountains to enter the village. In order to confirm this human-wildlife conflict, we installed a camera trap at the forest edge where the alleged “conflict Clouded Leopards” enter the village in order to gain a better understanding of the situation and assist the village in resolving this issue.
You can continue our journey in Part III here.
